1. Technical Field
The present invention relates to a communication control unit and a communication control method.
2. Description of the Related Art
Conventionally, when a communication terminal newly is to participate in a network, it is inevitably necessary to register the communication terminal in a domain, so as to acquire an IP address. For Example, in Japanese Patent Application Laid-open No. 2004-147128, there is disclosed a technique of mutually communicating between each communication terminal (image communication unit) which has been registered in a domain and an IP address is assigned to. According to the above technique, a session between each communication terminal is controlled by the use of a SIP (Session Initiation Protocol) proxy server.
Now, in general, the SIP specification is different depending on the vendors. Therefore, in order to communicate between communication terminals of different vendors using the above-mentioned prior art, it is necessary to provide, for each SIP specification applied to each communication terminal, an SIP proxy server appropriate to the applied specification. In this case, by attaching an identical domain name to each SIP proxy server, a different global IP address is assigned thereto, which requires complicated processing.
In order to improve the above, it is an object of the present invention to provide a communication control unit and a communication control method enabling a variety of communication terminals having not been registered in a domain to participate in a network without the need of complicated processing.